After the latest incident interrupted an interview during a live broadcast from the town’s Party In The Market family event this weekend, Mr Delahunty told the Press Association: “We have absolutely no idea who it is, but it sounds like someone from our area.

“Some people have told me that their children have started humming the song in the car.

“We have had calls from people who have found it hilarious, while some have raised their concerns, including our competitors, and a lot of people in the industry are aghast at how difficult it is to stop these people.

“For listeners under the age of 11 travelling to school, it can be a very offensive thing for them to hear, so I just want it to stop… but I would also love to see who it is and have them caught.”

Mr Delahunty said the hijacker uses a mobile transmitter to intercept the station’s output during live outside broadcasts and it can affect all or some areas that the station reaches. After the hacking on Sunday, the station was forced to “limit” its live broadcast and go back to the studio.

The watchdog has sent in experts to try and catch the hacker (Dominic Lipinski/PA)

“There’s absolutely nothing we can do,” he continued.

“The first time we reported it to the police, but they said they would have to catch him in the act. Our transmitter people can’t do anything because the person is using a mobile transmitter.”

Mr Delahunty added that the communications regulator Ofcom has sent a van with advanced equipment on three occasions to try and catch the hacker, but have so far been unsuccessful because they can only track him when he is broadcasting.

While he said the repeated hacking gave “evidence of stupidity rather than nastiness”, he warned: “It is an offence…imagine if it was a terrorist message or a phoney emergency call that could cause chaos for listeners.

“At the moment we are a victim, but we do apologise to listeners when it happens.”